![]() | You can help expand this article with text translated from the corresponding article in German. (April 2019)Click [show] for important translation instructions.
|
A meteotsunami or meteorological tsunami [1] is a tsunami-like sea wave of meteorological origin. Meteotsunamis are generated when rapid changes in barometric pressure cause the displacement of a body of water. In contrast to impulse-type tsunami sources, a traveling atmospheric disturbance normally interacts with the ocean over a limited period of time (from several minutes to several hours). [2] Tsunamis and meteotsunamis are otherwise similar enough that it can be difficult to distinguish one from the other, as in cases where there is a tsunami wave but there are no records of an earthquake, landslide, or volcanic eruption. [2] : 1036 Meteotsunamis, rather, are triggered due to extreme weather events including severe thunderstorms, squalls and storm fronts; all of which can quickly change atmospheric pressure. Meteotsunamis typically occur when severe weather is moving at the same speed and direction of the local wave action towards the coastline. The size of the wave is enhanced by coastal features such as shallow continental shelves, bays and inlets. [3]
Only about 3% of historical tsunami events (from 2000 BC through 2014) are known to have meteorological origins, although their true prevalence may be considerably higher than this because 10% of historical tsunamis have unknown origins, tsunami events in the past are often difficult to validate, and meteotsunamis may have previously been misclassified as seiche waves. [4] Seiches are classified as a long-standing wave with longer periods and slower changes in water levels. They are also restricted to enclosed or partially enclosed basins.
Meteotsunamis are restricted to local effects because they lack the energy available to significant seismic tsunami. However, when they are amplified by resonance they can be hazardous. [2] Meteotsunami events can last anywhere from a few minutes to a couple of hours. Their size, length and period is heavily dependent on the speed and severity of the storm front. They are progressive waves which can affect enclosed basins and also large areas of coastline. These events have produced waves over six feet in height and can resemble storm surge flooding. [3]
In April 2019, NOAA determined that 25 meteotsunamis, on average, impact the Eastern Seaboard of the United States every year. In the Great Lakes, even more of these events occur; on average, 126 times a year. [5] In some parts of the world, they are common enough to have local names: rissaga or rissague (Catalan), ressaca[ citation needed ] or resarca (Portuguese), milgħuba (Maltese), marrobbio or marrubio (Italian), Seebär (German), sjösprång (Swedish), abiki or yota (Japanese), šćiga (Croatian). [2] Some bodies of water are more susceptible than others, including anywhere that the natural resonance frequency matches that of the waves, such as in long and narrow bays, particularly where the inlet is aligned with the oncoming wave. [4] : 4 Examples of particularly susceptible areas include Nagasaki Bay, [2] : 1038–1040 [4] : 8 the eastern Adriatic Sea, [2] : 1046 [4] : 8 and the Western Mediterranean. [2] : 1044
Area | Country | Wave height [m] | Fatalities |
---|---|---|---|
Vela Luka (21 June 1978) [6] [2] : 1046 | Croatia | 5.9 | 0 |
Nagasaki Bay (31 March 1979) [4] | Japan | 5 | 3 |
Pohang Harbour[ citation needed ] | Korea | 0.8 | |
Kent and Sussex coasts (20 July 1929) [7] | UK | 3.5–6 | 2 |
Longkou Harbour (1 September 1980) [2] : 1044 | China | 3 | |
Ciutadella Harbour (15 June 2006) [4] | Spain | 4 | |
Gulf of Trieste [ citation needed ] | Italy | 1.5 | |
West Sicily [ citation needed ] | Italy | 1.5 | |
Malta [ citation needed ] | Malta | 1 | |
Chicago (26 June 1954) [4] | US | 3 | 7 |
Daytona Beach, FL (3–4 July 1992) [4] [8] | US | 3.5 | 0 |
Ciutadella Harbour & Alcudia [ citation needed ] | Spain | 1.8 | 0 |
Barnegat Inlet (13 June 2013) [9] | US | 1.8 | 0 |
Tolchester Beach (6 July 2020) [10] | US | ||
Hanko (7 August 2023) [11] | Finland | 0.58 | |
Lake Michigan Beach (2 April 2021) [12] | US | 0 |
In 1929, a wave 6 meters in height pulled ten people from the shore, to their deaths in Grand Haven, Michigan. A three-meter wave that hit the Chicago waterfront in 1954 swept people off of piers, drowning seven. [4] : 10 A meteotsunami that struck Nagasaki Bay on 31 March 1979 achieved a maximum wave height of 5 meters; there were three fatalities. [4] In June 2013, a derecho off the New Jersey coast triggered a widespread meteotsunami event, where tide gauges along the East Coast, Puerto Rico and Bermuda reported "tsunami-like" conditions. The peak wave amplitude was 1 foot above normal sea level in Newport, RI. In New Jersey, divers were pulled over a breakwater and three people were swept off a jetty, two seriously injured, when a six-foot wave struck the Barnegat Inlet. [5] [13]
A tsunami is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event.
Extreme weather includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Extreme events are based on a location's recorded weather history. They are defined as lying in the most unusual ten percent. The main types of extreme weather include heat waves, cold waves and heavy precipitation or storm events, such as tropical cyclones. The effects of extreme weather events are economic costs, loss of human lives, droughts, floods, landslides. Severe weather is a particular type of extreme weather which poses risks to life and property.
A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are sometimes called thundershowers. Thunderstorms occur in a type of cloud known as a cumulonimbus. They are usually accompanied by strong winds and often produce heavy rain and sometimes snow, sleet, or hail, but some thunderstorms produce little precipitation or no precipitation at all. Thunderstorms may line up in a series or become a rainband, known as a squall line. Strong or severe thunderstorms include some of the most dangerous weather phenomena, including large hail, strong winds, and tornadoes. Some of the most persistent severe thunderstorms, known as supercells, rotate as do cyclones. While most thunderstorms move with the mean wind flow through the layer of the troposphere that they occupy, vertical wind shear sometimes causes a deviation in their course at a right angle to the wind shear direction.
A meteorologist is a scientist who studies and works in the field of meteorology aiming to understand or predict Earth's atmospheric phenomena including the weather. Those who study meteorological phenomena are meteorologists in research, while those using mathematical models and knowledge to prepare daily weather forecasts are called weather forecasters or operational meteorologists.
A severe thunderstorm watch is a statement issued by weather forecasting agencies to advise the public that atmospheric conditions in a given region may lead to the development of severe thunderstorms within the region over a period of several hours. The criteria for issuing a watch varies by country, and may also include torrential rainfall and tornadoes. A watch may also be issued several hours ahead of the arrival of a mature and organized complex of storms, or more clustered or discrete storm activity.
The National Weather Service (NWS) is an agency of the United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weather-related products to organizations and the public for the purposes of protection, safety, and general information. It is a part of the National Oceanic and Atmospheric Administration (NOAA) branch of the Department of Commerce, and is headquartered in Silver Spring, Maryland, within the Washington metropolitan area. The agency was known as the United States Weather Bureau from 1890 until it adopted its current name in 1970.
A seiche is a standing wave in an enclosed or partially enclosed body of water. Seiches and seiche-related phenomena have been observed on lakes, reservoirs, swimming pools, bays, harbors, caves, and seas. The key requirement for formation of a seiche is that the body of water be at least partially bounded, allowing the formation of the standing wave.
A storm surge, storm flood, tidal surge, or storm tide is a coastal flood or tsunami-like phenomenon of rising water commonly associated with low-pressure weather systems, such as cyclones. It is measured as the rise in water level above the normal tidal level, and does not include waves.
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather, while high-pressure areas are associated with lighter winds and clear skies. Winds circle anti-clockwise around lows in the northern hemisphere, and clockwise in the southern hemisphere, due to opposing Coriolis forces. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the atmosphere (aloft). The formation process of a low-pressure area is known as cyclogenesis. In meteorology, atmospheric divergence aloft occurs in two kinds of places:
A tropical wave, in and around the Atlantic Ocean, is a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which moves from east to west across the tropics, causing areas of cloudiness and thunderstorms. Tropical waves form in the easterly flow along the equatorial side of the subtropical ridge or belt of high air pressure which lies north and south of the Intertropical Convergence Zone (ITCZ). Tropical waves are generally carried westward by the prevailing easterly winds along the tropics and subtropics near the equator. They can lead to the formation of tropical cyclones in the north Atlantic and northeastern Pacific basins. A tropical wave study is aided by Hovmöller diagrams, a graph of meteorological data.
This is a list of meteorology topics. The terms relate to meteorology, the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting.
This article describes severe weather terminology used by the National Weather Service (NWS) in the United States. The NWS is a government agency operating as an arm of the National Oceanic and Atmospheric Administration (NOAA) branch. It defines precise meanings for nearly all of its weather terms.
A mesoscale convective system (MCS) is a complex of thunderstorms that becomes organized on a scale larger than the individual thunderstorms but smaller than extratropical cyclones, and normally persists for several hours or more. A mesoscale convective system's overall cloud and precipitation pattern may be round or linear in shape, and include weather systems such as tropical cyclones, squall lines, lake-effect snow events, polar lows, and mesoscale convective complexes (MCCs), and generally forms near weather fronts. The type that forms during the warm season over land has been noted across North and South America, Europe, and Asia, with a maximum in activity noted during the late afternoon and evening hours.
A Pacific hurricane is a tropical cyclone that develops within the northeastern and central Pacific Ocean to the east of 180°W, north of the equator. For tropical cyclone warning purposes, the northern Pacific is divided into three regions: the eastern, central, and western, while the southern Pacific is divided into 2 sections, the Australian region and the southern Pacific basin between 160°E and 120°W. Identical phenomena in the western north Pacific are called typhoons. This separation between the two basins has a practical convenience, however, as tropical cyclones rarely form in the central north Pacific due to high vertical wind shear, and few cross the dateline.
The climate of California varies widely from hot desert to alpine tundra, depending on latitude, elevation, and proximity to the Pacific Coast. California's coastal regions, the Sierra Nevada foothills, and much of the Central Valley have a Mediterranean climate, with warmer, drier weather in summer and cooler, wetter weather in winter. The influence of the ocean generally moderates temperature extremes, creating warmer winters and substantially cooler summers in coastal areas.
Traditionally, areas of tropical cyclone formation are divided into seven basins. These include the north Atlantic Ocean, the eastern and western parts of the northern Pacific Ocean, the southwestern Pacific, the southwestern and southeastern Indian Oceans, and the northern Indian Ocean. The western Pacific is the most active and the north Indian the least active. An average of 86 tropical cyclones of tropical storm intensity form annually worldwide, with 47 reaching hurricane/typhoon strength, and 20 becoming intense tropical cyclones, super typhoons, or major hurricanes.
Severe weather is any dangerous meteorological phenomenon with the potential to cause damage, serious social disruption, or loss of human life. These vary depending on the latitude, altitude, topography, and atmospheric conditions. High winds, hail, excessive precipitation, and wildfires are forms and effects, as are thunderstorms, downbursts, tornadoes, waterspouts, tropical cyclones, and extratropical cyclones. Regional and seasonal phenomena include blizzards (snowstorms), ice storms, and duststorms.
Tsunamis affecting Britain and Ireland are extremely uncommon, and there have only been two confirmed cases in recorded history. Meteotsunamis are somewhat more common, especially on the southern coasts of England around the English and Bristol Channels.
{{cite web}}
: Missing or empty |title=
(help)